The present application relates to a manipulator operated by a human operator, and in particular, to a control system of controlling a manipulator suitable for the human operator to accurately conduct jobs in an unbearable environment and in cosmic space.
The U.S. patent Ser. No. 3,909,600 issued to R. E. Hohn on Sept. 30, 1975 describes a first coordinate for operations of a manipulator of an industrial robot the first coordinate corresponds to the rectangular coordinate of a manipulator arm.
In the conventional manipulator, the complex operations of the manipulator are likely to depend on the skill of the human operator.
For example, in a master-slave configuration, a master arm and a slave arm are provided with the same shape or an analogous shape, which consequently leads to cases where the master arm is of a structure unsuitable for the human operation, where the dimension of the master arm is sometimes so great that the operator himself or herself becomes to be a hindrance of the operation of the master arm, and where fine operations cannot be conducted.
In addition, in a remote manipulation, the field of vision of the operator is interrupted by the manipulator and hence the operator is required to shift the head to the right and/or to the left for the manipulation. In consequence, for example, an industrial television (ITV) is employed in this situation; however, a sufficient field of vision cannot be attained by a single image from a television camera, and if many television cameras are arranged for this purpose, there appear variations in relationships between images and the manipulator, which causes in some cases a confusion of the human operator.
Recently, with a rapid advance of the computer technology, there has been employed a computer to control a manipulator and a robot so as to develop a highly developed control operation. As an example, as described in pages 40 to 45 of an article of T. Arai et al., "Bilateral Control for Manipulators with Different Configurators", 1984, IECON '84; there is used a computer which conducts an operation of a coordinate transformation at a high speed to establish the one-to-one correspondence between the movements respectively of a master arm and a slave arm having the different shapes, respectively. In this article, there have also been described a velocity and a transformation of a force associated with a Jacobian matrix.
In addition, in the JP-A-61-252081, there has been described a method in which even in a case where there exist differences of the position and attitude between a master arm and a slave arm and hence the relationship of the one-to-one correspondence cannot be established by achieving a projective transformation therebetween so as to obtain an origin shared therebetween, the correspondence can be attained only by means of the apparatus having the coordinate correspondence establish function.
In addition, there has been published a technology in which an animated image of a robot is produced by an animation technology so as to be imaged by use of an industrial television to enable the teaching of the robot by use of the animated image, thereby conveniently attaining the result, which is the same as that attained by actually operating the robot.
The convention technologies above are still confined in the respective narrow technological fields and cannot be regarded as a completely satisfactory system technology including the human operations which is configured through discussion of the manipulator from a comprehensive viewpoint.
For example, in the above case of the high-speed coordinate transformation technology, for the master arm and the slave arm, matching is established with respect to the respective rectangular coordinate points and the positions of the tips of the respective arms and hence the ratio of motion, that is ratio of the velocity or distance associated with each arm is fixed.
In consequence, in a case when a fine work is to be accomplished by means of the slave arm, it is necessary for the master arm to conduct a fine operation similar to the fine operation required for the slave arm; and conversely, in a case where a great action is to be taken by the slave arm, it is similarly necessary for the master arm to conduct a great action.
As described above, the operation of the slave arm imposes a heavy load on the human operator and the realizability of the work depends on the skill of the operator.
In addition to the load of the operator, there arises a psychological load imposed on the operator in a case where the operation is conducted by visually checking an image displayed on an industrial television screen so as to operate the master arm with a direction of a television camera taken into consideration.
The JP-A-61-252081 proposes an effective solution to solve the problem above. In this method, the master arm and the slave arm can be independently controlled such that the coordinate correspondence is later established. In consequence, although the correspondence can be established in a broad range, there may appear a danger as a result of a wrong correspondence thus established. In addition, for the correspondence established in association with industrial cameras, since the master arm and the slave arms are independently processed, there are required the respective correspondences to be established between the cameras and the master arm and between the cameras and the slave arm, namely, the operations become to be complicated and hence this method is not practical in some cases.